Is this the decade of the dynasties?
All three are reaching toward North American leadership

, with Mr. Bush and Ms. Clinton running for president and Mr. Trudeau hoping to follow his father as prime minister in Canada's federal elections next month. All three are reaping the benefits of a famous family name. And all three are paying for the missteps of their family members, enduring the resentments spawned by their family members, suffering the consequences of the decisions of their family members.

In truth, dynastic politics always has been part of the culture of both countries, even the one to the south that was created in a rebellion against the ultimate institution of dynastic politics, the British crown. The second and sixth presidents of the United States bore the name Adams, the ninth and 23rd were named Harrison, the 26th and 32nd were named Roosevelt, and the 41st and 43rd (and perhaps the 45th as well) were named Bush. All that is without mentioning the Kennedys, who ran for president in 1960, 1968 and 1980 and who remain the royal family of American politics, an incongruous phrase when applied to a republic.

And in Canada, two Paul Martins (the father a Liberal Party cabinet member for four prime ministers, the son a Liberal prime minister himself) have been at the dizzying heights of Canadian leadership, the Mannings (Ernest was premier of Alberta for a quarter-century and his son, Preston, was founder of the Reform Party) have been giants in Western and Canadian federal politics, and no history of British Columbia could conceivably omit the Bennetts (W.A.C. Bennett was provincial premier for two decades and his son, Bill, held the post for more than a decade). The less said about the Fords of Ontario (best known for the drug-induced adventures of Rob, the former mayor of Toronto) the better.

Here in Maine, the Bush political dynasty  which produced more than a decade in the United States Senate, four years in the House, eight years in the vice presidency, a dozen in the presidency, eight years in the governor's chair in Florida, six years in the governor's mansion in Texas and time as director of Central Intelligence, chief U.S. delegate at the United Nations, chairman of the Republican National Committee and as the top American diplomat in Beijing  has a physical symbol.

It is an elegant but rugged compound on a spit of land angling onto the Atlantic that has charmed world leaders from Canada's Brian Mulroney to Russia's Vladimir Putin. It is called Walker's Point and once was owned by George Herbert Walker, one of the founders of amateur golf's Walker Cup and the grandfather of George Herbert Walker Bush (41st president) and great-grandfather of George Walker Bush (43rd president). It is not a coincidence that the Bush compound here in Maine is often compared to the Kennedy complex at Hyannis Port, also on the coast, 150 miles south of here.

Nor has the political class missed the symbolism of the construction of a new 3,000-square-foot cottage on the grounds of Walker's Point. It is being built by Jeb Bush, who already has used the Bush family compound to entertain top Republican donors amid the sea spray and salt-water air of coastal Maine.

Jeb Bush, Hillary Clinton and Justin Trudeau, to be sure, are reaping the benefits of being parts of great political families, where politics was served with supper and where great men and women walked through their homes and their lives.

They have enjoyed the triumphs  three presidential victories for the Bushes, two for the Clintons, plus four federal election victories (1968, 1972, 1974, 1980) for Pierre Elliott Trudeau, father to Justin Trudeau. But they also suffered the defeats, including George H.W. Bush's loss in a high-profile Texas Senate race in 1970 and his failure to win re-election in 1988, Jeb Bush's defeat in his first campaign for Florida governor in 1994, Bill Clinton's defeat in his campaign for a second term as Arkansas governor in 1980, Hillary Clinton's failure to beat Barack Obama for the 2008 Democratic presidential nomination and Mr. Trudeau's defeat in the Canadian federal election of 1979. Both Mr. Clinton and George W. Bush lost early House races.

Those lessons are seared into the memories of famous political families, and they never were so prominent a part of the nation's political psyche as they were in the year 2000, when the losing families in the two most prominent Senate races in 1970 (the senior George Bush in Texas, the senior Albert Gore in Tennessee) faced off in a presidential race that went into a 36-day overtime.

All three of the last names now angling for North American leadership are associated with high points in their countries' histories, the Bushes with the fall of communism and the Gulf War, the Clintons with the roaring 1990s economy, the Trudeaus with the star turn the father took on the international stage when, whether in or out of office from 1968 to 1984, the senior Trudeau was a symbol of Canada's status as an economic and moral force.

Then again, Jeb Bush has to answer for his brother's war in Iraq  questions that have produced awkward moments for him  while Ms. Clinton battles ''Clinton fatigue,'' a phenomenon that suggests she would begin a new round of Clinton scandals.

And though his father, who died in 2000, has not been premier since June 30, 1984, there is a touch of Trudeau fatigue in Canada. The senior Mr. Trudeau, who positioned Canada as a formally bilingual nation, remains a controversial figure north of the 49th parallel, with his many constitutional efforts and his National Energy Program still reviled in the country, especially in the West, where alienation from Ottawa began in the Trudeau years and has spiked intermittently since then.

These perils came into focus this summer, when Jeb Bush was asked a leading question about his advisers, some of whom inevitably worked for the two Presidents Bush. "If they've had any executive experience, they've had to deal with two Republican administrations," he told a voter at the Iowa State Fair in August. "Who were the people who were presidents, the last two Republicans? I mean, this is kind of a tough game to be playing, to be honest with you. I'm my own person."

David Shribman, a Pulitzer Prize winner in journalism, is executive editor of the Pittsburgh Post-Gazette.